The present invention relates to a women""s disposable sanitary napkin for external use and more specifically to a women""s disposable sanitary napkin that is provided with conformable corrugations in its whole structure, which makes it possible to adapt the sanitary napkin to the wearer""s undergarment according to her needs.
Women""s disposable sanitary napkins are articles widely known in the state of the art that comprise an absorbent core sandwiched between two layers known as top sheet and lining sheet. The top sheet is permeable to fluids and its function is to allow the passage of the menstrual fluid towards the absorbent core, thus keeping the fluid away from the wearer""s body. It can be comprised of a layer of a material other than a fabric or composed of a perforated plastic film for performing the function.
The lining sheet is generally impermeable to or resistant to the passage of liquids and is used to prevent the fluid absorbed by the absorbent core from leaking. It may comprise a non-perforated plastic sheet or any other material having such features.
The absorbent core is composed absorbent fibers and/or particles such as synthetic cellulosic or textile fibers such as rayon, polyester and the like. Its purpose is to contain the vaginal exudates. The absorbent core may optionally contain a superabsorbent material having a varying range of particle sizes and be may distributed either uniformly throughout the core or alternatively in discrete regions of the core, for example, as a layer, as a film, or as individual particles. One example of a conventional superabsorbent material that can be used is sodium polymethacrylate.
The conventional features in a woman""s disposable sanitary napkin include a shape that adapts to the woman""s anatomy, it should be capable of quickly absorbing liquids, it is preferably releasably affixed to the undergarment during use, and it is preferably discreet and comfortable.
The conventional women""s disposable sanitary napkin deforms from its initial configuration due to the wearer""s movement changes, for the movement tends to conform the napkin to the geometry of the space between the wearer""s thighs This deformation has been found to cause discomfort to the wearer and may also result in premature leakage.
Previous attempts to overcome these problems have tried to optimize the efficiency of those disposable products by using static concepts of the body shape in the pulp and improving the absorption of the menstrual fluid. Examples of articles of the state of the article the purpose of which is the anatomical adaptation include the hourglass shape used in women""s sanitary napkins, for example in U.S. Pat. No. 3,805,790 (Kimberly-Clark) and U.S. Pat. No. 4,758,241 (Elissa D. Papajohn). The configuration takes into account the space between the wearer""s thighs close to the vaginal region, thus providing an improvement over rectangular-shaped articles, but the women""s napkins did not take into account the individuality of the space between the wearer""s thighs and the variety of undergarment used nowadays.
Another example of a women""s sanitary napkin has a corrugated absorbent core, for example in U.S. Pat. No. 3,411,504 (J. A. Glasman). The women""s sanitary napkin in this patent includes an absorbent core provided with longitudinal embossed lines for a faster flow of the menstrual fluid. However, the napkin design in this patent did not take into account the wearer""s anatomy.
Still another example of a women""s sanitary napkin is disclosed in U.S. Pat. No. 3,954,107 (Colgate Palmolive). This sanitary napkin is provided with two parallel longitudinal absorbent cores having a channel therebetween whose function is to collect the fluid and direct same to the longitudinal ends of the article, not aiming at the women anatomy or comfort.